Nutrition Bites - Phytosterols lower cholesterol levels in a dose-dependent manner

Phytosterols are compounds found naturally in plants that are structurally similar to cholesterol. Good food sources include whole grains, unrefined plant oils, nuts, seeds, and legumes. It has been recognized for many years that phytosterols reduce total and LDL cholesterol levels in humans, which is why the National Cholesterol Education Program recommends adults consume 2 grams of phytosterols daily to help protect against cardiovascular disease. This quantity is only attainable through the use of supplements or plant sterol-enriched foods. A recent study sought to determine whether cholesterol-lowering effects could be achieved with lower doses of phytosterols (1).

The study was a highly controlled feeding trial in which participants consumed phytosterol-deficient diets plus supplemental beverages providing 0, 400, or 2000 mg phytosterols/day. All participants rotated through the three 4-week treatment conditions in randomized order, with 1 week between treatments. Under each experimental condition, intestinal cholesterol absorption and fecal cholesterol excretion were measured. The researchers found that both moderate and high intakes of phytosterols significantly increased fecal cholesterol excretion, with the higher dose eliciting a greater effect. In addition, high phytosterol intake significantly reduced LDL cholesterol levels, and a nonsignificant trend was observed for moderate intake.

In summary, although supplemental sources of plant sterols produce the greatest effect, even moderate phytosterol intake – such as that obtained from a diet rich in plant-based foods – provides cholesterol-lowering effects in humans.

Adapted from:
Racette SB, Lin X, Lefevre M, Spearie CA, Most MM, Ma L, Ostlund Jr RE. Dose effects of dietary phytosterols on cholesterol metabolism: a controlled feeding study. Am J Clin Nutr; Nov. 2009. [Epub ahead of print]

Good Food Sources of Phytosterols